Start the Car With a Dead Key Fob Battery

Last updated: June 12, 2026

The Citroën Berlingo (Mk2/B9, 2008–2018) — in both Multispace passenger and van forms — uses a conventional flip-key remote, not a keyless push-button system. That is good news when the fob battery dies: a flat coin cell on the Berlingo Mk2 only stops the remote lock and unlock buttons. The car itself starts exactly as normal because the immobiliser chip in the key head needs no battery at all.

So if your Berlingo’s remote has gone quiet, do not panic about being stranded. You unlock with the metal blade, slide the key into the ignition and turn it — the engine fires regardless of the coin cell. The steps below walk through it and the battery swap.

Start the Berlingo Mk2 with a dead fob

1. Press the button on the fob to flip the metal blade out (if the button is too weak to flip it, pull the blade out by hand against its spring).
2. Unlock the driver’s door with the blade (next section) and get in.
3. Insert the key into the ignition barrel on the steering column as you always do.
4. Turn the key to start. The barrel’s coil reads the transponder chip in the key head — which carries no battery — and the immobiliser releases the engine.

Unlock the doors with the emergency key blade

1. Flip out the metal blade from the fob.
2. Insert it into the lock cylinder on the driver’s door and turn to unlock. On the Berlingo the driver’s lock is exposed in the handle, with no cover to remove.
3. Once inside, the interior central-locking switch releases the passenger doors, sliding doors and tailgate.

The immobiliser note — why it still starts

Unlike modern keyless Citroëns, the Berlingo Mk2 reads its key through an induction coil wrapped around the ignition barrel. That coil powers the passive transponder chip in the key head by induction, the same way a contactless card works, so it never relied on the fob coin cell. The coin cell only feeds the long-range radio for remote locking — which is why a dead battery loses the buttons but never the ability to start.

Replace the fob battery

The Berlingo Mk2 flip-key remote uses a single CR1620 3V lithium coin cell — a thinner, smaller cell than the CR2032 used elsewhere, so check the marking before buying. Undo the small screw or split the fob case along its seam, ease the halves apart, lift the old cell and fit the new one the same way up. Reassemble and press a lock button near the car a couple of times; if the remote does not respond, it may need re-syncing with the ignition on.

Frequently Asked Questions

Will my Berlingo start with a completely dead fob battery? Yes. The ignition reads the key’s transponder by induction with no battery needed, so a flat coin cell never stops it starting — only the remote buttons.

Why won’t my remote lock the van any more? The CR1620 cell has died. The radio that the lock and unlock buttons use runs off that cell. Fit a fresh one and the buttons return.

What battery does the Berlingo Mk2 fob take? A CR1620 lithium coin cell — not the more common CR2032. Match the printed code.

The blade unlocked the driver’s door only — how do I open the rest? Get in and press the interior central-locking switch; it releases the other doors, the sliders and the tailgate.

My new battery is in but the remote still does nothing — now what? The remote can drop sync after a battery change; many Berlingo remotes re-pair by switching the ignition on and pressing the lock button, though some need a dealer or locksmith to recode.

If a warning light or immobiliser fault code came up, you can decode it on our sister site autodtcs.com.